REPRODUCTIVE HISTORY OF THE MOLE, 215 
other animals, and both are stages in the normal formation of 
the female genital system of Homo (12). The imperforate vagina 
is a normal stage in the female human embryo, and this solid 
vagina becomes patent in very much the same way as does that. 
of the mole—by desquamation of its central cells. 
{h) The moje is exceptional in that the opening up of the 
solid vagina is so long delayed. 
(2) Again, it is not without parallel that a vagina once formed 
should become occluded again, only to be reopened when next. 
functional activity demands a passage; these phases have been 
established by Hill (5) with regard to the median vagina of 
Perameles. 
Bibliography. 
(1) Errenne Grorrroy (St. Hilaire).—Cours de histoire 
naturelle des Mammifeéres. Paris, 1829. 
(2) Tuomas Betu.—Article “ Insectivora” in Todd’s Cyclopedia 
of Anatomy and Physiology, vol. ii. p. 1005. 1839. 
(3) RicHarD OwEn.—Comparative Anatomy and Physiology of 
the Vertebrates, vol. iii. p. 609. 1868. 
(4) Lionet E. Apams.—Manchester Memoirs, vol. xlvii. No. 4. 
1903. 
(5) James P. Hini.—Proc. Linn. Soc. New South Wales, 1889, 
pt. 1., March 29th, p. 42. 
(6) F. Woop-Jones.—The Development and Malformations of 
the Glans and Prepuce. Brit. Med. Journ., Jan. 15th, 
ILO. 
(7) Various authors quoted by G. EK. H. Barrert-HAminron.—A 
History of British Mammals, pt. vii. p. 37. 
(8) H. E. Forrest.—The Fauna of Shropshire, 1899, p. 45. 
(9) Morrison Watson.—On the Female Generative Organs of 
Hyena crocuta. Proc. Zool. Soc. Lond., May 1877, 
p- 369. 
(10) Henry C. Cuapman.—Observations on the Female Gene- 
rative Apparatus of Hyena crocuta. Proc. Acad. Nat. Sei. 
Philadelphia, 1888, p. 189. 
(11) Joun Hunrer.—Essays and Observations. Edited by Owen, 
1861, vol. i. p. 188. 
(12) F. Woop-Jonzs.—The Development and Malformations of 
the Urogenital Passages, etc. Brit. Med. Journ., 
Dec. 17th, 1904. 
EXPLANATION OF THE PLATES. 
Puate I. 
Fig. 1. Section of the pelvis of the 27 mm. embryo showing the lower ends of the 
Mullerian ducts. 
2. Section of pelvis of 27 mm. embryo, slightly lower than fig. 1, showing the 
extreme limit of the caudal bend of the urethra, and the tissue in which 
the Mullerian ducts end. 
